99 grand am indescribable sound tap/growl/whir/rattle after water pump change
svrwthr
05-31-2008, 12:32 PM
Think this one will be easy to figure out? Then please help me because I have 5 people who work on vehicles are quite knowledgeable listen to this problem and it still baffles them. This is thorough so bare with length.
'99 Grand Am 2.4 twin cam 110,000 miles regular oil changes. Water pump went out on it and began the lengthy task of disassemblinge every god knows thing to get to it. For some humor I started this in an un heated garage back in late January. Anyways, I put new water pump in with everything seated just fine. Put the pins in the timing hole on the exhaust and intake camshaft sprockets with tightness across the two then lined up the pin holes/tick marks on the crankshaft sprocket with tightness in the chain from intake sprocket down to crankshaft sprocket leaving the slack of the chain on the water pump sprocket side. I didn't retract the chain tensioner though because I thought it was regulated by oil pressure. I put everything back together and fired it up, Chain grinding sound until tensioner finally extended. Engine ran fine but with a slight cough every so often. I said S*&t! out of time. I took the timing chain cover back off and found I had slipped 1 tooth on the exhaust side. I didn't know about the push down on tensioner to release it until I took tensioner out and the auto parts store told me how to work it. I went back home and timed out everything again with tightness through exhaust to intake to crank sprockets and slack to the water pump sprocket again and popped out the tensioner to pick up slack. Perfect!, all lined up, good tension on chain throughout. I put everything back together and fired her up again. OMG I never heard it sound so good. She purred like a kitten :smokin: and I was all smiles in the cold a55ed air. Finally finished, I thought.
That was the good part now here comes the problems. I drove to work on a Monday (30 miles one way) all was good. Tuesday all going good until I came home. As I was about to shut off the engine I heard what was not quite a tick or a tap from the riders side of engine and down by the balancer. I thought maybe one of the 26 bolts on the timing chain cover came loose and the balancer was hitting it. I thought this because the sound was at the same rate of turn as the balancer and was coming from that same spot. I didn't want to take off all the wheel well again until weekend because I needed a car to get to work and cannot call into work. So I drove it thinking it was minor and would tear it apart on the weekend. Wednesday same sound and by Thursday getting home I had a sound what can only be described as bike chain rubbing on it's chain guard at idle, we all have heard that before when were kids. This sound was still on the passenger side but not by the balancer but more towards the water pump on the passenger side but higher up. I spent the weekend milling over the sound and drove it to work on Monday to have one of my back yard mechanics hear the noise. By then though the sound has resonated more toward the rear of the engine by the water pump and no longer sounding like that chain rubbing metal, it has become part that, part growl, part rattle at idle. If I idle it up slightly the sound goes away. Add more RPM and you can start to hear the sound but slightly less. Let off on the gas and it growls down. The car has good speed, good start, good shut off and good idle. Here is what I have done and specifics in last few days. (yes 4 months working on it, to damn cold and to damn frustrated and to poor to take to certified mechanic and don't want to be ripped off)
after 3rd person listened to this and was baffled I decided to check timing and tensioner again plus exhaust valves since that is where the timing slipped and have heard it could damage the valves. During break down, timing is fine. Took valve cover off and pulled out lifters, cleaned and set aside in order. Pulled on the valves and checked for play and looked over springs. All good. Put everything back together timed it out and fired it back up still the same sound at idle only with slight same sound at higher rpm. I gave up to give a break to my mind and finally had a half a55ed mechanic come over and we stethascoped it. The sound seemed to come from the altenator. We took belt off to eliminate it. Wasn't the problem. With belt off we stethascoped it again on the water pump (fine) then across the valves. Had some resonance on the drivers side but not as much as on the timing chain cover itself. Now refresher, the sound is still lower part of engine backside toward water pump resonating sometimes to the drivers side and sometimes toward the water pump. Guy was to come back with oil pressure sensor to rule out crankshaft, pick up. He also thought maybe it was a main bearing or a bearing riding one another. I said it can't be because it would sound like a knock and not the sound we have and also that we would hear the sound from all directions not just the rear of the engine. Also I only changed the water pump and didn't touch anything internal lower. And he agreed. Not ruling it out at this time though.
5th and final person I had come over we took the ignition module off the spark plugs and checked spark plugs. Waaaaayyy over .050-.060 that is required. Before we changed them we did a compression check to completely rule out the valves and pistons. From the drivers side over to the passenger side we got 160, 160, 160, 150. He said that was great compression for the miles on the car and that the piston 1 went 60-90-150 while turning the engine over and that we may have stopped to soon but 150 was still good. He told me that it may have slipped a tooth again and to take timing cover off and check the chain and timing again and he'd come back over. I have cover off, timing is perfect and chain is tight all the way around and I have been waiting for 2 days for him to come back. Now I come here and ask anyone if they have heard similar or can give me some guidance to a frustrating problem. A match and some gas, a stick of dynamite are not options here. I still owe on it and it is in excellent shape body wise and is worth repairing but not at over a grand I will be charged by a repair shop. Please help with any thoughts/ideas. Thank You.
'99 Grand Am 2.4 twin cam 110,000 miles regular oil changes. Water pump went out on it and began the lengthy task of disassemblinge every god knows thing to get to it. For some humor I started this in an un heated garage back in late January. Anyways, I put new water pump in with everything seated just fine. Put the pins in the timing hole on the exhaust and intake camshaft sprockets with tightness across the two then lined up the pin holes/tick marks on the crankshaft sprocket with tightness in the chain from intake sprocket down to crankshaft sprocket leaving the slack of the chain on the water pump sprocket side. I didn't retract the chain tensioner though because I thought it was regulated by oil pressure. I put everything back together and fired it up, Chain grinding sound until tensioner finally extended. Engine ran fine but with a slight cough every so often. I said S*&t! out of time. I took the timing chain cover back off and found I had slipped 1 tooth on the exhaust side. I didn't know about the push down on tensioner to release it until I took tensioner out and the auto parts store told me how to work it. I went back home and timed out everything again with tightness through exhaust to intake to crank sprockets and slack to the water pump sprocket again and popped out the tensioner to pick up slack. Perfect!, all lined up, good tension on chain throughout. I put everything back together and fired her up again. OMG I never heard it sound so good. She purred like a kitten :smokin: and I was all smiles in the cold a55ed air. Finally finished, I thought.
That was the good part now here comes the problems. I drove to work on a Monday (30 miles one way) all was good. Tuesday all going good until I came home. As I was about to shut off the engine I heard what was not quite a tick or a tap from the riders side of engine and down by the balancer. I thought maybe one of the 26 bolts on the timing chain cover came loose and the balancer was hitting it. I thought this because the sound was at the same rate of turn as the balancer and was coming from that same spot. I didn't want to take off all the wheel well again until weekend because I needed a car to get to work and cannot call into work. So I drove it thinking it was minor and would tear it apart on the weekend. Wednesday same sound and by Thursday getting home I had a sound what can only be described as bike chain rubbing on it's chain guard at idle, we all have heard that before when were kids. This sound was still on the passenger side but not by the balancer but more towards the water pump on the passenger side but higher up. I spent the weekend milling over the sound and drove it to work on Monday to have one of my back yard mechanics hear the noise. By then though the sound has resonated more toward the rear of the engine by the water pump and no longer sounding like that chain rubbing metal, it has become part that, part growl, part rattle at idle. If I idle it up slightly the sound goes away. Add more RPM and you can start to hear the sound but slightly less. Let off on the gas and it growls down. The car has good speed, good start, good shut off and good idle. Here is what I have done and specifics in last few days. (yes 4 months working on it, to damn cold and to damn frustrated and to poor to take to certified mechanic and don't want to be ripped off)
after 3rd person listened to this and was baffled I decided to check timing and tensioner again plus exhaust valves since that is where the timing slipped and have heard it could damage the valves. During break down, timing is fine. Took valve cover off and pulled out lifters, cleaned and set aside in order. Pulled on the valves and checked for play and looked over springs. All good. Put everything back together timed it out and fired it back up still the same sound at idle only with slight same sound at higher rpm. I gave up to give a break to my mind and finally had a half a55ed mechanic come over and we stethascoped it. The sound seemed to come from the altenator. We took belt off to eliminate it. Wasn't the problem. With belt off we stethascoped it again on the water pump (fine) then across the valves. Had some resonance on the drivers side but not as much as on the timing chain cover itself. Now refresher, the sound is still lower part of engine backside toward water pump resonating sometimes to the drivers side and sometimes toward the water pump. Guy was to come back with oil pressure sensor to rule out crankshaft, pick up. He also thought maybe it was a main bearing or a bearing riding one another. I said it can't be because it would sound like a knock and not the sound we have and also that we would hear the sound from all directions not just the rear of the engine. Also I only changed the water pump and didn't touch anything internal lower. And he agreed. Not ruling it out at this time though.
5th and final person I had come over we took the ignition module off the spark plugs and checked spark plugs. Waaaaayyy over .050-.060 that is required. Before we changed them we did a compression check to completely rule out the valves and pistons. From the drivers side over to the passenger side we got 160, 160, 160, 150. He said that was great compression for the miles on the car and that the piston 1 went 60-90-150 while turning the engine over and that we may have stopped to soon but 150 was still good. He told me that it may have slipped a tooth again and to take timing cover off and check the chain and timing again and he'd come back over. I have cover off, timing is perfect and chain is tight all the way around and I have been waiting for 2 days for him to come back. Now I come here and ask anyone if they have heard similar or can give me some guidance to a frustrating problem. A match and some gas, a stick of dynamite are not options here. I still owe on it and it is in excellent shape body wise and is worth repairing but not at over a grand I will be charged by a repair shop. Please help with any thoughts/ideas. Thank You.
skibum1111
05-31-2008, 02:09 PM
Did you replace the timing chain guides while you had it apart? Sounds like the chain is hitting metal somewhere.
svrwthr
06-01-2008, 12:04 PM
Thank You and the answer is no. Do you really think that the chain guides could be the problem? There is no noticeable wear on them and the raised guide walls (edges) on each side of them are complete with no broken or missing edges. I am not at the capability in resources to start putting $40 here $40 there into it if the problem continues after changing out things. I can get the resources but is an option I would like to avoid at the moment but will take it into consideration Thank You.
I have been thinking about changing the chain, tensioner and now maybe the guides as well. Chain is 40, tensioner is 40-90 depending on parts store and guides are around 40. It may be something as simple as those items since it is such a difficult thing to pinpoint. And usually when a problem is this difficult it turns out to be something simple. Before I try these changes and have to put together and possibly take apart over and over I will wait and see with more ideas from responses. I will keep everyone updated that reads this.
I have been thinking about changing the chain, tensioner and now maybe the guides as well. Chain is 40, tensioner is 40-90 depending on parts store and guides are around 40. It may be something as simple as those items since it is such a difficult thing to pinpoint. And usually when a problem is this difficult it turns out to be something simple. Before I try these changes and have to put together and possibly take apart over and over I will wait and see with more ideas from responses. I will keep everyone updated that reads this.
svrwthr
06-15-2008, 05:48 PM
Update. Bought new chain, guides and tensioner. Old chain had about 1/4" extra length and boy those guides felt nice and tight. set my pins in exhaust and intake ran chain and set cam pin points. Everything perfectly aligned and tightened. Timing right on and I thought this is it baby. It is gonna work. Set charger on battery (since I wore battery down from previous tests and checks with mechanics) and waited for charge. Fired her over and sure as shit, same bleeping noise!!!!! Still coming from back riders side of engine. Everything is tight to specs. Forgot correct term but the only thing I see may be missing is the washer in between the cam sprocket and timing cover which hadn't had one when I dismantled it but books say that some models come with it. I doubt is that. Next step is I checked exhaust manafold to exaust pipe connection where a lot of sound is near and seems to be slightly loose. Maybe I should change the doughnut at that connection but I am at least going to try and crank down on 3 bolts. It could very well be rattling at low idle and when I let off after revving, and this noise did gradually start like something was getting loose. If that is not problem I will try a new water pump. After that I give up. Will still keep this post updated. Maybe a link to sound byte for others to hear.
svrwthr
06-29-2008, 04:49 PM
After 6, count them, 6, people that rebuild cars and repair cars on regular basis (no not certified mechanics but very knowledgeable), the problem has been solved. I put car together to take to my cousin, a crane operator and pit mechanic for a local truck racer, I first had a malfunction other than the original. My spring coil broke driving out of garage. Probably from the damn car sitting up jacks for months. After I changed that I got the car to my cousins. He was baffled as well and decided to ramp the front end. He pulled a little plastic cover off the bottom of the engine and transmission. Jabbed around with a screw driver and said, "Yep, there it is." I said "What?". He said, "just what I thought but wasn't sure because of the sound resonating to rear of engine. Your flywheel is cracked." Smiles gleamed from me after I went under and looked at it too.
I carefully drove back home so I didn't send the flywheel through the housing and now comes the long task of taking both driveaxles off and attempting to remove the flywheel without removing the transmission completely. Yes it can be done but saying how.
So if any of you change a geared water pump and get a strange noise that isn't the new water pump failing, and cannot determine what it is or where it is coming from,don't leave out checking that flywheel too. I guess this in not an uncommon thing for a flywheel to take a shit when after changing a geared water pump.
I carefully drove back home so I didn't send the flywheel through the housing and now comes the long task of taking both driveaxles off and attempting to remove the flywheel without removing the transmission completely. Yes it can be done but saying how.
So if any of you change a geared water pump and get a strange noise that isn't the new water pump failing, and cannot determine what it is or where it is coming from,don't leave out checking that flywheel too. I guess this in not an uncommon thing for a flywheel to take a shit when after changing a geared water pump.
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